Drugs presently used in treatment of human or animal ectoparasitic infestations are either dermal irritants or contain as active ingredients components having at least a potential liability for neurotoxic side effects to the host.
Preparations which are not strongly ovicidal need to be reapplied as successive hatchings occur. The ideal drug for treatment of ectoparasites should be active against the ova as well as the adult and nymphal forms, and should be relatively non-toxic to the host.
In contrast to drugs used by inuction, compositions designed to be used as shampoos or body washes must either exert their parasiticidal and ovicidal effects within a very short time, or must resist washing off during the course of ablutions.
It has been found that certain aminopropionic acids, especially the N-alkyl aminopropionic acids, alone or in equilibrium with their salts, fulfill all of these criteria. The aminopropionic acids are well known materials. They have heretofore been used as surface active agents and have been incorporated in cosmetic preparations as such. For example, a "cosmetic" type of liquid shampoo containing 10% of the sodium salt of N-Coco-.beta.- aminopropionic acid, 8.25% triethanolamine lauryl sulfate, 2.5% of coconut diethanolamide, sufficient lactic acid to adjust the pH to 4.5-5.0, perfume, color and water q.s. ad. 100% is known. This shampoo is not known to be an ectoparasiticide.
It is the object of this invention to provide new safe and effective toxicants for lice, mites, other insects and their ova. This and other objects of the invention will become apparent to those skilled in the art from the following detailed description.